A new study has come up with a way to separate the fibres in polyester cotton fabrics, using a salt commonly used in baking.

Scientists at the University of Copenhagen added ammonium carbonate to scraps of polyester cotton in ethylene glycol. They then heated up the solution to 160° with the result that the fibres separated into layers.

“This catalytic approach outperformed conventional acid/base and metal catalysis in selectively recovering and upcycling cotton-based materials,” say the study’s authors.

“Our method offered a traceless, environmentally friendly, and practical approach for polyester recycling and cotton recovery, representing a significant step toward sustainable, closed-loop production of plastics and textiles.”

The salt – also known as Hartshorn – is widely used in Scandinavian and German baking for crackers and biscuits.

The study was published in the journal ACS Sustainable Chemistry & Engineering.